python libraries are available in common

Deprecate virtualenv jail, it had no walls.

Other than refactoring, the config semantics changed
slightly.  I'm unhappy with the import-by-value issue,
"from process.globals import config" will not update
config during initialization, so you need to call
load_config before importing any other tools/ files.

TODO:
* moar docs

Change-Id: I5bc6741852b95b67c6354c4634369ab7c7423fd8
Merge "python libraries are available in common"